本文整理汇总了C#中System.Data.Objects.ObjectContext.ObjectStateManager属性的典型用法代码示例。如果您正苦于以下问题:C# ObjectContext.ObjectStateManager属性的具体用法?C# ObjectContext.ObjectStateManager怎么用?C# ObjectContext.ObjectStateManager使用的例子?那么恭喜您, 这里精选的属性代码示例或许可以为您提供帮助。您也可以进一步了解该属性所在类System.Data.Objects.ObjectContext
的用法示例。
在下文中一共展示了ObjectContext.ObjectStateManager属性的2个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: using
int orderId = 43680;
using (AdventureWorksEntities context =
new AdventureWorksEntities())
{
ObjectStateManager objectStateManager = context.ObjectStateManager;
ObjectStateEntry stateEntry = null;
var order = (from o in context.SalesOrderHeaders
where o.SalesOrderID == orderId
select o).First();
// Attempts to retrieve ObjectStateEntry for the given EntityKey.
bool isPresent = objectStateManager.TryGetObjectStateEntry(((IEntityWithKey)order).EntityKey, out stateEntry);
if (isPresent)
{
Console.WriteLine("The entity was found");
}
}
示例2: ApplyItemUpdates
private static void ApplyItemUpdates(SalesOrderDetail originalItem,
SalesOrderDetail updatedItem)
{
using (AdventureWorksEntities context =
new AdventureWorksEntities())
{
context.SalesOrderDetails.Attach(updatedItem);
// Check if the ID is 0, if it is the item is new.
// In this case we need to chage the state to Added.
if (updatedItem.SalesOrderDetailID == 0)
{
// Because the ID is generated by the database we do not need to
// set updatedItem.SalesOrderDetailID.
context.ObjectStateManager.ChangeObjectState(updatedItem, System.Data.EntityState.Added);
}
else
{
// If the SalesOrderDetailID is not 0, then the item is not new
// and needs to be updated. Because we already added the
// updated object to the context we need to apply the original values.
// If we attached originalItem to the context
// we would need to apply the current values:
// context.ApplyCurrentValues("SalesOrderDetails", updatedItem);
// Applying current or original values, changes the state
// of the attached object to Modified.
context.ApplyOriginalValues("SalesOrderDetails", originalItem);
}
context.SaveChanges();
}
}